The subject matter described herein relates generally to imaging detectors, such as computed tomography (CT) detectors, and more particularly, to a fault tolerant cooling system for CT detectors.
CT detectors may include a detector rail having a plurality of detector components positioned thereon. The detector components also may include a collimator having openings formed therein to direct x-rays emitted from a subject to a scintillator. The collimator separates the x-rays along the scintillator. The x-rays are then converted to light waves with a plurality of photodiodes positioned behind the scintillator. An analog-to-digital convertor converts the analog light waves to digital signals that are then used to generate an image of the subject.
In operation, the detector components may generate a considerable amount of heat which may affect the operation of the CT detector. For example, the heat may cause the detector components to shift on the detector rail. As such, the openings of the collimator may become misaligned with openings in the scintillator, leading to scatter or noise in the image generated by the CT imaging system. Additionally, some detector components are sensitive to changes in temperature. For example, the photodiodes may overheat or become damaged if exposed to large changes in temperature or cause image artifact due to increased electronic noise due to leakage current from photodiode and/or A/D device. This may be particularly problematic given that large amounts of heat may be generated by the analog-to-digital converter which is positioned adjacent to the photodiodes.
Accordingly, at least some known imaging systems include a cooling system to cool the CT detector. The cooling system may include, for example, fans, heat sinks, temperature sensors, or the like. In operation, the temperature sensors provide an indication of the various operational temperatures at certain points within the cooling system. However, when a single temperature sensor fails, at least one known imaging system is shut down. A technician may then be contacted to repair the failed temperature sensor. As a result, a single failed temperature sensor may cause the imaging system to be taken out of operation for an extended period of time until the technician can repair and/or replace the failed temperature sensor.